In the ad ecosystem, publishers would like to keep site profitable by selling ads to advertisers and provide display opportunity (on web pages, social media, etc). The advertisers would like to win these opportunities through participation of auctions. Ad exchange is responsible for making communications between supply side (publisher) and demand side (advertisers) by allowing auctions for display opportunities. Most popular auction mechanism for multiple items is generalized second-price auction (GSP) [1]} [2]}, where after each bidder places a bid, the highest bidder gets the first slot and the second-highest wins the second slot and so on, but the highest bidder only needs to pay the price bid by the second-highest bidder. In practice, Cavallo et al. [3]} re-designed the search ads selling system that achieves the properties analogous to those held by GSP for supporting a variety of ads sizes, decorations, and other distinguishing feature.
